Subclassed QPlainTextEdit, how can call in other class?

  • This is my main that creates the RepairDevices window:

    #include "repairdevices.h"
    #include <QtWidgets>
    int main(int argc, char * argv[])
        QApplication app(argc, argv);    
        RepairDevices win;;
        return app.exec();

    RepairDevices.cpp has slot setDirty:

    public slots:    
        void setDirty(QString text);

    I have subclassed QPlainTextEdit, to a class named 'notifierText'.
    I have promoted a QPlainTextEdit, named sn_txt, to this class.
    The sn_txt is in my form, created with Qt Designer.

    This is my class' source:

    notifierText::notifierText(QWidget *parent) : QPlainTextEdit(parent)
        QString thistext = this->toPlainText();
        connect( this, SIGNAL(textChanged(QString)), parent, SLOT(setDirty(thistext)) );    

    Obviously, the 'parent, SLOT(...' is wrong.
    Ho can I call the setDirty function in RepairDevices.cpp?

  • It's RepairDevices that has to connect to notifierText not the other way around

  • I did it like this in RepairDevices constructor:

    But I get a warning:
    QObject::connect: No such signal QPlainTextEdit::textChanged(QString)

    And it's not working.
    What am I doing wrong?

  • Qt Champions 2017

    Does notifierText have a Q_OBJECT macro ?

  • Hi mrjj.
    I demoted it to QPlainTextEdit, I don't use the notifierText class.

  • Qt Champions 2017

    Hi :)
    ok so sn_txt is now a 100% normal QPlainTextEdit and not your class?
    Did you clean, rebuild all after changing back?

  • Yes it 's a pure QPlainTextEdit .
    I cleaned and rebuild but the same happens.

  • Qt Champions 2017

    show the new current code then.
    It normally just works.

  • This is the connection in RepairDevices' constructor:


    This is the declaration of the function:

    public slots:
        void setDirty(QString txt);

    This is the function:

     void RepairDevices::setDirty(QString txt)
         qDebug() << "text=" << txt;   

  • When I change to textChanged(), it works.
    But I don't have the text of the sn_txt.

    And I see here: void QPlainTextEdit::textChanged()

  • Qt Champions 2017

    @Panoss said in Subclassed QPlainTextEdit, how can call in other class?:


    i dont think it has version where it emits the whole text. lineEdit has.

    so you must use QPlainTextEdit::textChanged() and

    void RepairDevices::setDirty()
    qDebug() << "text=" << ui->plaintext->toPlainText();

  • The reason I subclassed it, was because I wanted the class to connect to RepairDevices 's slot.
    (that is, the code: connect blah blah to be in the class)
    This is not possible, so it's canceled.
    Thank you for your help.

  • Qt Champions 2017


    Well the normal signal does not have QString but in a subclass
    you could easy make a new signal that would have and
    then emit it in the subclass and it would be as you wanted.

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